A roadside bomb has killed three British soldiers, injuring a further six, in
Afghanistan's Helmand Province.

The soldiers were from The Royal Highland Fusiliers, 2nd Battalion The Royal Regiment of Scotland, spokesman for Task Force Helmand, Major Richard Morgan, said.

They died after their vehicle, a Mastiff armoured patrol vehicle once described by prime minister David Cameron as offering "the best-known protection" against bombs, was struck by an improvised explosive device in the Nahr-e Saraj district of Helmand province on Tuesday.

The three soldiers were riding in a Mastif armoured vehicle when they were struck by an improvised explosive device (Julian Simmonds)

They received immediate medical attention and were evacuated by air to the Military Hospital at Camp Bastion but could not be saved.

"Their deaths come as a great loss to all those serving in Task Force Helmand. Our thoughts and prayers are extended to their family and friends at this difficult time," Maj Morgan said.

Following the three deaths, Mr Cameron said the country had paid a "very high price" for the work it was doing in Afghanistan.

Speaking on ITV's Daybreak, Mr Cameron said: "It is important work because it's vital that country doesn't again become a haven for terrorists, terrorists that can threaten us here in the UK.

"But today our thoughts should be with the families and friends of those that have suffered."

The soldiers were in a vehicle searching for IEDs on a tarmac surface when the device exploded.

The blast came on the third day of what the Taliban has called its spring offensive, which it said would take aim at British, US and other foreign military bases and diplomatic areas.

The militant group's leadership vowed that "every possible tactic will be utilised in order to detain or inflict heavy casualties on the foreign transgressors."

The insurgents warned they would infiltrate enemy ranks to conduct "insider attacks" and target military and diplomatic sites with suicide bombers.

The fighting is a key test, as the international coalition is scheduled to hand over security responsibilities to Afghan forces next year.

Yesterday's attack marks the biggest loss of life for British troops in Afghanistan since March last year, when six British servicemen were killed when a roadside bomb struck their armoured vehicle.

A total of 444 British soldiers and 2,207 US troops have died since fighting began in the country back in 2001.

Britain, which is scaling down operations in Afghanistan ahead of its complete withdrawal in 2014, currently has around 9,000 troops in Southern Afghanistan serving in a US-led coalition.

The Taliban and other insurgent groups make heavy use of roadside bombs. They are among the deadliest weapons in the Afghan war for civilians.

Far to the north, in Archi district in the province of Kunduz, a roadside bomb killed two people, including a local police commander who had been credited with reducing the number of insurgent attacks in his area, said Abdul Nazar, a local council member.

Commander Miran and his driver were killed and two other police officers wounded when the car they were driving toward Kunduz City was destroyed by a bomb hidden by the road, said Nazar.